Regression analysis of the nuclear symmetry energy for relativistic mean-field models
Regression analysis for the symmetry energy within a sample of relativistic mean-field models of nuclear matter is performed. The selected models consistently meet the experimentally obtained limitations. A proposed measure of the importance of adding the fourth-order term to the symmetry energy is analyzed. As a result of the research, it became possible to arrange the models and perform two-dimensional and one-dimensional linear regression analyses. The one-dimensional regression analysis between the input parameters confirms the appropriateness of introducing the division of the sample of considered models into four separate classes representing four statistically different fits. An addi…
Stabilization of 1D solitons by fractional derivatives in systems with quintic nonlinearity
AbstractWe study theoretically the properties of a soliton solution of the fractional Schrödinger equation with quintic nonlinearity. Under “fractional” we understand the Schrödinger equation, where ordinary Laplacian (second spatial derivative in 1D) is substituted by its fractional counterpart with Lévy index $$\alpha$$ α . We speculate that the latter substitution corresponds to phenomenological account for disorder in a system. Using analytical (variational and perturbative) and numerical arguments, we have shown that while in the case of Schrödinger equation with the ordinary Laplacian (corresponding to Lévy index $$\alpha =2$$ α = 2 ), the soliton is unstable, even infinitesimal diffe…